Retrievable subsurface well tool



Dec. 3, 1963 J. D. KEITHAHN 3,112,795

RETRIEVABLE SUBSURFACE WELL TOOL Filed Nov. 14, 1960 4 Sheets-Sheet 1E60. E00 1a;

i I w w v v a a g INVENTOR. Zf/L 101v D. K51 THHHN Dec. 3, 1963 J. D.KEITHAHN 3,112,795

RETRIEVABLE SUBSURFACE WELL TOOL Filed Nov, 14, 1960 4 Sheets-Sheet 2INVENTOR. (704 mm D. Em rum/1v Dec. 3, 1963 J. D. KEITHAHN 3,112,795

RETRIEVABLE SUBSURFACE WELL TOOL Filed Nov. 14, 1960 4 Sheets-Sheet 3 lz ao 3a.

United States Patent M 3,112,795 RETRIEVABLE SUBSURFACE WELL TOOL JulianD. Keithahn, Houston, Tex., assignor to Baker Oil Tools, Inc., LosAngeles, Calif, a corporation of California Filed Nov. 14, 1960, Ser.No. 68,954 16 Claims. ((31. 166-420) The present invention relates tosubsurface well tools, and more particularly to packers and anchorsadapted to be run and set in well casing, and similar conduit strings,disposed in well bores.

An object of the invention is to provide a subsurface well tool adaptedto be operated by manipulation of a tubular string secured to the welltool, the well tool embodying a valve device shiftable between open andclosed conditions by longitudinal movement of the tubular string througha relatively long stroke, the well tool being pressure balanced so thatpressure differentials cannot open the valve device inadvertently fromits closed condition.

Another object of the invention is to provide a subsurface well tool, asabove set forth, in which the valve device can be shifted readily fromclosed to open condition by manipulation of the tubular string despitethe presence of comparatively high pressure differentials on the tool.

A further object of the invention is to provide a subsurface well toolembodying a valve device that can be readily shifted to a closedcondition by manipulation of a tubular string secured to the well tool,and in which the valve device becomes automatically latched in itsclosed condition and incapable of being opened inadvertently bypressurre differentials to which the well tool is subjected, the valvedevice still being easily shifted to an open condition despite thecontinued imposition of pressure differential on the tool.

This invention possesses many other advantages, and has other objectswhich may be made more clearly apparent from a consideration of a formin which it may be embodied. This form is shown in the drawingsaccompanying and forming part of the present specification. It will nowbe described in detail, for the purpose of illustrating the generalprincples of the invention; but it is to be understood that suchdetailed description is not to be taken in a limiting sense, since thescope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURES 1 and la together constitute a combined side elevational andlongitudinal sectional view through an apparatus embodying theinvention, with ports disposed in condition for moving the toollongitudinally through a well casing, FIG. 1a constituting a lowercontinuation of FIG. 1;

FIGS. 2 and 2a are views similar to FIGS. 1 and 1a disclosing the toolanchored in packed-0E condition in the well casing;

FIGS. 3 and 3a are views corresponding to FIGS. 1 and 1a disclosing thetool after having been released from the well casing;

FIG. 4 is a side elevational view of the control portion of the packer;

FIG. 5 is a cross-section on an enlarged scale taken along the line 5-5on FIG. 1;

FIG. 6. is a cross-section on an enlarged scale taken along the line 6-6on FIG. 1;

FIG. 7 is a cross-section on an enlarged scale taken along the line 77on FIG. 1a.

As disclosed in the drawings, a retrievable well packer A is adapted tobe anchored to a well casing B against movement in both an upward anddownward direction,

Patented Dec. 3, 1963 and to be packed-oil against the wall of the wellcasing to prevent leakage of fluid thereby. The lower portion C of thetool is a set-down type of well packer, the upper portion D of the toolbeing constituted as an anchor to prevent upward movement of theapparatus in the well casing. The apparatus is lowered in the wellcasing on a tubular string B, such as tubing or drill pipe,extending tothe top of the well bore, and through which fluent substances underpressure, such as cement slurry, acid, and the like, can be pumped,flowing through the central passage of the tool for discharge from itslower portion.

The well packer A includes a central main body or mandrel 19 having apassage 11 therethrough that may be of relatively large diameter. Theupper portion of this body is threadedly secured to a top body sub 12having a threaded box 13 for attachment to the lower threaded pin end 14of the tubular string E. The mandrel 10 of the body extends downwardlythrough the entire length of the tool A and has a lower threaded pin 15for threaded attachment to a lower section of tubing or a lower tool F.The lower portion 16 of the body is actually constituted as a lower bodysub having a threaded box 17 threadedly secured to the lower pin end 18of the main section of the body or mandrel 10.

The upper portion D of the tool includes an anchor body 19 surroundingthe mandrel 10, and which may be laterally spaced therefrom to providean annular space 20 therebetween. This annular space extends upwardlythrough a housing 21 for a control valve and a balance sleeve 22, thelower end of the housing being threadedly attached to the upper end ofthe anchor body 19. The anchor body has a plurality of circumferentiallyspaced cylindrical bores 23 therethrough, each containing a pistongripping element 24 slidable radially therein. Each cylindrical bore 23is open to the interior of the anchor body 19 and also to the exteriorthereof. The piston gripping elements 24 have external wickers or teeth25 that may face in an upward direction to anchor the apparatus A to thewell casing B against upward movement therewithin. As shown, a pluralityof cylinders 23 and gripping elements 24 are provided in longitudinalalignment with one another, there being sets of such longitudinallyaligned gripping elements 24 disposed around the circumference of theanchor body 19.

The anchor body has external grooves 26 on opposite sides of alignedcylinders in each set, these grooves merging into companion grooves 27formed in the outer portions of the longitudinally aligned grippingelements 24. Disposed in the body and gripping element grooves areretainer members and spring seats 28 in the form of bars suitablysecured to the anchor body, as by use of screws 29. Each bar retains thepiston gripping elements 24 properly oriented with their wickers orteeth 25 facing in an upward direction. Each bar also serves as theouter spring seat for a helical compression spring 30 disposed in andbearing against the socket portion 31 of each piston gripping element24, tending to urge each piston gripping element inwardly to its fullestextent, but yieldably permitting its inward and outward radial movement.

The piston gripping elements 24 are expanded outwardly whenever fluidpressure differential, sumcient to overcome the compressive force of thesprings 30, is present interiorly of the anchor body 19. In the presentcase, such fluid pressure is derived from the exterior of the tool belowthe anchor portion D of the apparatus, which pressure can pass throughthe annular space 20 between the body or mandrel 10 of the tool and theanchor body 19 to each of the cylinders 23. The fluid pressuredifferential for expanding the gripping elements is actually derivedfrom a location in the well casing below the set-down type of wellpacker portion C of the tool, passing from such location into theannular space 20 through a path described hereinbelow. Fluid pressure inthe cylinders 23 urges each piston 24 outwardly, leakage of fluid alongeach piston being prevented by a suitable piston ring or side seal ring33 in the piston slidably sealing against the Wall of its companioncylinder 23.

The inner mandrel or body It) is shiftable longitudinally with respectto the anchor body 19 and the housing 21 secured thereto to open andclose the annular passage 20. Thus, the mandrel carries a valve head 34threadedly attached to the top or body sub 12, which has a suitableperipheral seal ring 35 thereon, the head and seal ring being adapted tomove downwardly within a cylindrical seat 36 formed in the valve headportion 37 of the housing 21. When the mandrel 10 is shifted downwardlyrelative to the anchor body 19 and the housing 21, its valve head 34 andseal ring 35 are moved Within the cylindrical seat 36, closing the upperportion of the annular passage 20, and enabling the pressure below thetool and tending to elevate the mandrel ill to be counterbalanced, so asto prevent inadvertent opening of the valve device. The annularbalancing sleeve 22 is disposed in an annular cylinder portion 38 of thehousing 21. This sleeve or piston 22 includes a head 39 initiallyoccupying an upward position adjacent to a cylinder head 49, the pistonhead being slidable along the wall of the cylinder 38. Leakage of fluidbetween the piston and cylinder is prevented by a suitable piston ring41 carried by the piston and slidably sealing against the wall of thecylinder 38. The piston has a skirt 42 depending from its head 39, whichis slidable along and within the upper portion of the anchor body 19,leakage of fluid therebctween being prevented by suitable side seal 43mounted in the anchor body and slidably sealing against the outerperiphery of the skirt 42. The piston device 22 has an internal diametersubstantially greater than the external diameter of the body or mandrel19, so as not to obstruct the annular passage 29 between the body 10 ofthe tool and the housing 21 and anchor body 19 surrounding the body 10.

Integral with the balancing member 22 are upwardly extending arms 44formed by providing circumferentially spaced longitudinal slots 45 in anupper portion of the balance member, these arms terminating in upperfingers or heads 4-6 initially disposed in an internal groove 47 in thehousing 21, the heads 46 tending to spring inwardly and initiallyengaging the periphery of the tool body. When the mandrel It is moveddownwardly within the anchor body 19 and housing 21, to dispose thevalve head 34 and seal 35 within the valve seat 36, and thereby closethe valve portion of the device, a peripheral groove 48 in the mandrelit) below the valve head 34 is located opposite the fingers or heads 46,such fingers or heads then springing inwardly Within such groove 43 andout of the internal circumferential groove 47 in the valve head. Anypressure in the closed annular passage 20 will now act in a downwarddirection on the piston head 39, such downward force being transmittedthrough the fingers 46 to the lower side 49 of the mandrel groove 48,thereby tending to urge the body or mandrel it) in a downward direction.The lower side 49 of the mandrel groove and the lower inner portions dof the fingers or heads are inclined in an inward and upward direction,so that upward movement of the mandrel relative to the fingers or headswill earn the latter outwardly when they are disposed opposite theinternal housing groove 47. When the fingers or heads are disposed inthe mandrel groove 48, they are out of the housing groove 47 and arefree to move into the lower smaller diameter portion 51 of the housing21, the balance device 22 then being free from the housing 21 andcapable of exerting a downward force on the body or mandrel it The fluidpressure within the tool A when in its set conditions tends to act in anupward direction over the crosssectional area of the body it) and itsvalve head 34, designated by the letter S, tending to shift the mandrel10 in an upward direction with respect to the valve seat 36, which wouldeffect opening of the valve. Such upward movement is counterbalanced, inthe present instance, by making the annular area R of the balance piston39 substantially equal to the area S. The fluid pressure within the toolis acting in a downward direction on the piston over the area R, andsuch downward force is transmitted through the latch fingers or heads 46to the mandrel it). Thus, substantially equal and opposite forces arebeing exerted by the fluid pressure on the body or mandrel 1t precludingits inadvertent shitting under the action of fluid pressure to a valveopening condition. If desired, the area R can be made slightly greaterthan the area S so that the fluid pressure is actually tending tomaintain the body or mandrel 10 in a downward direction, to insureagainst inadvertent opening of the valve device and the annular passage20.

The valve device can readily be shifted to an open condition merely byelevating the tubular string E, which will shift the body or mandrel it)upwardly with respect to the anchor body 19 and the housing 21. There isvery little, if any, resistance by fluid pressure to such upwardmovement of the mandrel, in view of the balancing action of the fluidpressure acting in an upward direction over the area S and in a downwarddirection over the area R. Accordingly, the mandrel 10 and the balancesleeve 22 latched thereto are moved upwardly until the fingers 46 aredisposed opposite the circumferential groove 47 in the housing 21,whereupon the lower shoulder or side 49 of the mandrel groove can camthe fingers outwardly into the housing groove 47, the fingers therebybeing free to the mandrel groove 48 to allow the mandrel 19 to moveupwardly to its fullest extent, free from restraint by the fingers 46.

The upper anchor portion D of the apparatus is secured to the downwardlyacting set down type of well packer C. This packer includes a normallyretracted packing device 55 surrounding the tubular body or mandrel 19,which includes an inner support sleeve 56 threadedly attached to thelower end of the anchor body 19 and spaced laterally from the body toprovide a continuation of the annular passage 20 through which fluid canpass. Surrounding the support sleeve is a packing structure 57, such asa rubber or rubber-like packing sleeve, which is normally retracted. Theupper end of the packing structure 5'7 is adapted to engage the lowerend of the anchor body 19, which serves as an upper abutment. It alsoengages an upper gauge ring 58 threaded on the lower end of the anchorbody 19, and serving as an outer extension of the upper abutment. Thelower end of the packing sleeve 57 is engageable with a lower abutment59 slidable on the support sleeve 56 and threadedly conected to anexpander sleeve portion or sleeve extension 60, which is integral with alower expander 61 of generally frusto-conical shape adapted to coactwith a plurality of circumierentially spaced lower slips 62 foranchoring the apparatus in the Well casing. When the packing structure57 is in retracted position, the lower abutment 59 may engage anexternal lower flange 63 of the support sleeve 56. The support sleeveand the expander sleeve portion 6t) may be non-rotatably secured to oneanother, while permitting their relative telescopic movement, byattaching a key 64 to the flange portion of the support sleeve which isslidable in a longitudinal keyway or slot 65 in the interior of theexpander leeve 6t).

Fluid can pass through the annular space 66 surrounding the apparatusand around the expander 61, flowing inwardly through a plurality ofcircumferentially spaced ports or openings 6'7 in the expander sleeveportion 69 to its interior and then flowing upwardly through the annularpassage 2%, discharging through the valve seat 36 and into the annulus63 around the body it) and the tubular string E. Downward movement ofthe tubular string E and body 10 relative to the members surrounding thebody will, as has been described above, place the valve head 34 inengagement with the valve seat 36 to close the annular passage aroundthe body.

A connector sleeve 69 is slidably mounted on the exterior of the body10, its upper portion extending Within the expander 61 and terminatingin an upper stop or flange 70 that projects outwardly and is adapted toengage the upper end 71 of the expander. The lower end of the connectorsleeve 69 may rest upon the upper end or stop portion 72 of the lowerbody sub 16. Surround ing the connector sleeve is a slip sleeve 73slidable thereon and having a plurality of longitudinally extendingcircumferentially spaced grooves 74 in which the slips 62 are laterallymovable. These slips each include a lower drag portion 75 adapted tofrictionally engage the inner wall of the well casing B, being urgedoutwardly thereagainst by one or a plurality of compression springs 76engaging the bases of the grooves 74 and the drag portions 75 of theslips. The slips 62 include upper anchor portions 77 having downwardlyfacing wickers or teeth 78 adapted to engage and embed themselves in thewall of the well casing B, to prevent downward movement of the slipstherealong when expanded outwardly by the expander 61. The expander hasa downward and inwardly inclined tapered surface 79 adapted to coactwith companion inner tapered surfaces 80 on the anchor portions 77 ofthe slips.

Outward expansion of the slips 62 under the influence of the springs 76is limited by a retainer ring 81 encom passing the central portions ofthe slips and received within external grooves 82 therewithin. Outwardmovement is also limited by engagement of lower terminals 83 of theslips, below the drag portions 75, with an upper rim 84 of a stop andcontrol sleeve or member 85 surrounding the body 10 of the tool andreleasably connected thereto by a lock device. The stop and controlmember or sleeve 85 and the slip sleeve 73 are secured together by aplurality of longitudinally extending screws 86, so that they move as aunit. When the stop and control member 85, slip sleeve 73 and slips 62are disposed in a lower position on the body, such as illustrated inFIG. la, an upper inner flange 87 on the stop and control member isengageable with a split snap ring 88 mounted in a peripheral groove 89in the connector sleeve 69, to limit the upward position of theconnector sleeve relative to the stop and control member 85, as well asrelative to the slip sleeve 73. This snap ring has a lower beveledcorner 90 inclined in a downward and inward direction, and an upperbeveled corner 91 inclined in an upward and inward direction.

Such beveling is obtained so that a laterally movable control pin 92slidable radially in a companion bore 93 in the control member 85 canride over the snap ring 88 during operation of the apparatus.

The slips 62 are prevented from having substantial longitudinal movementrelative to the slip sleeve 73 by engagement of the lower ends 94 of theslips with the upper end of the control member 85 and also by engagementof the retainer ring 81 with an upper external flange 95 of the slipsleeve. When the slip sleeve 73 is moved downwardly, its upper flange 95engages the retainer ring 81, which engages the lower sides of the slipgrooves 82 to pull the slips 62 downwardly in the well casing. When theslip sleeve 73 and the control member 85 are moved upwardly, the upperend of the control member engages the lower ends 94 of the slips andshifts them upwardly along the wall of the well casing. The slipsthemselves are of the rocker type, in that the anchor portions 77 areremoved from engagement with the wall of the well casing when thesprings 76 are permitted to force the drag members '75 into full contactwith the wall of the well casing. However, when the expander 61 movesdownwardly within and behind the anchor portions 77 of the slips, thelatter will rock outwardly about the upper parts of the drag portions 75as a fulcrum on the casing, to

6 shift the teeth 78 outwardly against the well casing and embed themtherewithin.

The packer body or mandrel 10 moves downwardly with respect to the partsthat surround it in order to engage the valve head 34 with its companionvalve seat 36, to expand the packing structure 57 against the wall ofthe well casing B, and to engage the expander 61 with the anchorportions 77 of the slips and expand the latter outwardly into anchoringengagement with the wall of the well casing. The ability of the body 10of the tool to move in the manner just described is dependent upon thecontrol mechanism provided between the slip mounting portions 73, of theapparatus and the body 10 of the tool.

As disclosed in the drawings, the laterally or radially shiftablecontrol pin 92 has its inner portion yieldably disposed within a controlslot or groove in the periphery of the lower body sub 16 by a leafspring 101 engaging the outer end of the control pin 92 and secured tothe control member in any suitable manner, as by a screw 102. Thecontrol slot or groove includes a circumferential groove portion 103terminating at one end in a stop segment 104 that extends between anupper stop flange 105 of the sub and the lower side 106 of thecircumferential groove, being secured thereto as by welding material107. Another segment 1015 is suitably secured to the sub 16, as bywelding, and this segment is spaced arcuately from the stop segment 104to provide a longitudinal inclined slot 109 communicating with anextension of the slot or opening 110 extending completely through thestop flange 105. The lower end of the segment 108 terminates above thelower side 106 of the circumferential groove 103 to provide acommunicating opening 111 between the circumferential groove portion 103and the longitudinal inclined slot or groove portion 109 through whichthe control pin 92 passes from one slot portion into the other portion.It is to be noted that the segments are so disposed that thelongitudinal slot portion 109 defined therebetween is preferablyinclined in an upward direction toward the right.

The apparatus can only be set in the well casing upon removal of thecontrol pin 92 from the circumferential groove portion 103. Movement ofthe control pin 92, the outer control mechanism 35 surrounding the body10 of the tool, and the connector sleeve 69, as well as movement of theslips 62, is resisted or prevented by the frictional engagement of thedrag portions 75 of the slips against the wall of the well casing B. Asa result, the tubular string E and body 10 of the tool can be movedupwardly to insure that the control pin 92 is in the lower portion ofthe circumferential groove 103, which location can be provided bycausing an upwardly facing shoulder 115 on the body sub 16 to engage thelower end of the control member 05, such as shown in FIG. la. With thiscondition pertaining, the tubing string E and body 10 are rotated to theright, which will turn the lower body member 16 within the control pin92 until the latter passes relatively through the communicating passage111 between the circumferential groove portion 103 and the inclinedgroove or slot portion 109 and engages the in clined wall 116 of thestop segment 104. The body 10 of the tool can now be lowered, thecontrol pin 92 passing relatively upwardly through the inclined slotportion 109 and through the opening 110 in the flange to a positionthereabove. The control pin actually does not move longitudinally, butthe body 10 and its groove 100 lower with respect thereto, the downwardmovement of the control pin 92 being resisted by the friction dragportions 75 of the slips. Downward movement of the body can nowcontinue, to effect closing of the valves 34, 36 and setting of thetool. The control pin 92 engages the lower end 90 of the snap ring 88and will, at first, prevent downward movement of the'connector sleeve 69with the body of the tool. However, upon engagement of the lower end ofthe support sleeve 56 with the upper end of the connector sleeve, thesnap ring 88 will force the control pin 92 outwardly so that the lattercan, in etfect, ride over the snap ring to a position thereabove, andthereby enable the setting of the well packer to be completed. After thecontrol pin 92 rides relatively past the snap ring, the connector sleeve69 may drop downwardly until its upper stop flange 70 again engages theexpander shoulder 71.

The apparatus A is run in the well casing with the parts in the positiondisclosed in FIGS. 1 and la, the control pin 92 being disposed in thelooking or circumferential groove portion 163. During the loweringaction, the upper side 1% of the groove will engage the pin and resultin pulling of the slip mechanism downwardly within the casing B andalong the casing wall. The inner flange 87 of the control member d5engages the snap ring 83 and insures the downward pulling of theconnector sleeve 6? with the body it and the control member. The contactof the stop flange 7th with the expander shoulder 71 insures downwardmovement of the expander and its sleeve portion 69, which will cause thelower abutment 59 to engage the flange 63 of the support sleeve 56 andpull the latter downwardly in the well casing with it. Since the supportsleeve is connected to the anchor portion 19 of the apparatus, thelatter is also pulled downwardly in the well casing. At this time, thepiston gripping elements 24 are in their retracted position, being heldin such position by the springs 33 and being precluded from inadvertentoutward expansion by the fact that fluid is flowing upwardly along theexteriors of the piston elements and also along their interiors, becauseof the fact that the annular passage 2a is open. Also at this time, thepliant, elastic packing structure 57 is in its retracted position sincethe lower abutment 59 is disposed downwardly to its maximum extent withrespect to the upper abutment or anchor body 19, 58. The anchor body 19and housing 21 are precluded from moving relatively upwardly along themandrel or body 10 of the tool to prevent engagement of the valve head34 With the valve seat 36, thereby insuring that the annular passage 26remains open.

As stated above, because of the fact that the annular passage 2% isopen, lowering of the tool through fluid in the well casing or well borewill cause such fluid to pass upwardly through the tubular body member1% and into the tubular string E thercabove, this fluid also passingrelatively around the exterior of the lower portion of the apparatus andthen through the ports 67 to the interior of the expander sleeve so, andcontinuing upwardly through the annular passage 2i? and the valve seat36 into the annulus 68 between the tubular string E and casing 12 abovethe packer apparatus A. Fluid also flows relatively around the outsideof the packing structure 57 itself into the annulus 68 between thetubular string and easing above the packer apparatus.

After the setting location of the well packer in the casing has beenreached, the tool is lowered a short additional distance in the wellcasing and is then elevated so that the body it of the tool is movedupwardly with respect to the control member 85 and pin 92, the controlpin then being disposed adjacent to the lower side 1166 of thecircumferential groove 103. The tubular runningin string E and body itare now turned to the right to rotate the body sub 15 and its groove 1%relative to the pin, whereby the pin 92 passes relatively into the lowerend of the inclined slot portion 169. Thereafter, the tubular string Eand body 10 of the tool are lowered. Downward movement of the body 16 ofthe tool can continue relative to the control member 85 and its pin 92since the latter then passes relatively upwardly through the entireinclined slot portion 169, 11) to a position above the upper stop flange165 of the sub 16. As described above, downward movement of the controlmember 85 and pin 2; is resisted by the drag portions 75 of the slips.

Downward movement of the body It now continues, the valve head 34 andseal ring 35 moving downwardly into the cylindrical valve sea 36 toclose the annular pass "e 20, the downward movement of the body 10 thenmoving the housing 21 and anchor body 1-9 and support sleeve 56therewith, the packing structure 57 and the lower abutment 59 also beingmoved downwardly for the purpose of shifting the expander sleeve portion69 and the expander 61 downwardly, accompanied by the connector sleeve69. The expander 61 moves downward toward the slips 62, which areprevented from moving downwardly by engagement of their drag portions 75with the wall of the well casing B. The connector sleeve 6? movesdownwardly with the expander 61 and the body 169 and within the slipstructure, the snap ring 88 cumming the control pin 92 out of the wayand allowing the snap ring to move past the control pin, which will nowslide upon the periphery of the connector sleeve. The downward movementof the body it and the parts surrounding it, with the exception of theslip structure surrounding the connector sleeve 69, will now continueuntil the expander 61 moves within and behind the anchor portions '77 ofthe slips, shifting the latter outwardly into engagement with the wallof the well casing. When this occurs, the expander 61 cannot movedownwardly any further. Accordingly, the continued downward movement ofthe body it) of the tool causes the anchor portion or upper abutment Ito move toward the lower abutment 59, which is prevented from movingdownwardly by being connected to the expander 61, compressing orshortening the packing sleeve 57 and expanding it outwardly into sealingengagement with the wall of the well casing. The parts are now in thecondition illustrated in FIGS. 2 and 2a.

As described above, upon downward movement of the body 10 within theanchor portion D and housing 21 of the tool, the peripheral groove 48 ofthe body is disposed opposite the latch fingers or heads 46, the lattersnapping into such groove and out of the housing groove 4-7, whereuponthe fingers or heads are adapted to bear against the lower shoulder 49on the mandrel, and then being disposed below the internal housinggroove &7 and adapted to slide downwardl along the housing portion 51,at least to a small extent. The balance device 22 is now in condition tootlset any pressure differentials in the apparatus, or there'oelow, thatwould otherwise tend to shift the body or mandrel l9 upwardly andinadvertently open the valve and the annular passage 2t! between thebody 10 of the tool and the anchor portion D and the packing device 55.

A suitable operation can now be performed with the set packer A. Thus,fluid under pressure is pumped down the tubular string E and through thebody or mandrel 10. Such fluid under pressure is also imposed on thefluid in the well bore below the set packing structure 55, passingthrough the ports 67 and into the annulus 20 between the mandrel l6 andthe anchor portion D and housing 21 connected to the anchor body. Thefluid pressure acts on the gripping members 24 and urges them outwardlyinto gripping engagement with the wall of the well casing. In the eventthe apparatus is subjected to high pressure diife-rentials, theanchoring action of the gripping members 24 against the well casing willprevent upward pumping or movement of the packer apparatus A in the wellcasing. At the same time, as has been noted above, such fluid pressurein the annulus 2d between the body or mandrel 10 and the housing 21 actsin a downward direction on the piston 39, the downward force beingimposed through the latch heads, as on the mandrel shoulder 49 urgingthe body or mandrel it in a downward direction and offsetting thetendency of the fluid pressure acting over the area S of the mandrel andtending to shift it in an upward direction.

After the operation in the well bore has been complcted, the tool A canbe released from the well casing B and removed therefrom, if desired. Ifthe fluid pressure has been relieved, release will occur simply as theresult of elevating the tubing string E and the body or mandrel it inthe casing. Even if fluid pressure has not been relieved, the releasestill can occur as the result of elevating the tubing string and body inthe casing. because of the hydraulic counterbalance feature, the fluidpressure is substantially balanced on the body or mandrel 10, so thatthe latter can be shifted upwardly [with exertion of comparativelylittle force on the tubular string B. At first the body moves upwardlyto carry the valve head 34- upwardly within the cylindrical valve seat36, and also to carry the fingers or heads 46 upwardly with it until thelatter are disposed opposite the release groove 47 in the housing 21,whereupon the body or mandrel 10 will cam the latch heads or heads 46outwardly free from the groove 4- 3. The mandrel 10 can then shiftupwardly to the extent required, the valve head and its seal moving outof the valve seat 36 in order to open the annular passage 2% around themandrel 1t), thereby enabling the fluid pressure to be equalizedinternally and externally of the apparatus. Following equalizing of thefluid pressure, the springs 39 shift the piston gripping elements 24 totheir retracted position free from engagement with the wall of the wellcasing.

During the initial phase of upward movement of the mandrel ill, theupper end 72 of the body sub 16 will engage the lower end of theconnector sleeve 69 and carry the latter upwardly with the body untilits upper end 7% engages the upper end of the support sleeve 56,whereupon the support sleeve and the anchor portion D connected theretoare shifted upwardly with the body it to move the upper abutmentconstituted by the anchor body 19 and gauge ring 58 away from the lowerabutment 59, which will permit the packing sleeve 57 to retract to itsinitial position. The support sleeve d6 moves upwardly with the bodydill and the connector sleeve 69 until its lower flange 63 engages thelower abutment 59, which will then elevate the expander sleeve portion6t? and the expander 61 from the anchor portions 77 of the slips 62,allowing the springs 76 to rock the drag portions 75 of the slips backinto full surface contact with the wall of the well casing and pivot theanchor portions 77 inwardly from engagement with the wall of the wellcasing. The expander 61 can move upwardly of the slips until the controlmember 85 engages the upwardly facing shoulder 115 on the lower body subis or its flange 37 engages the snap ring 88. The control pin 92 itselfmoves automatically into its locking circumferential groove portion 1%inasmuch as it merely rides upon the upper beveled end 91 of the snapring and past this ring, then engaging the inclined end 126lof the bodysub, riding past the flange m and back into the circumferential grooveportion -3. The control pin 92 can shift outwardly against the force ofthe leaf spring ltll, which will shift it inwardly into the groove 103after it rides past the stop flange 105.

The parts are now in the position they occupy during elevation of theapparatus in the well casing, which is illustrated in FIGS. 3 and 3a.During such elevating movement through fluid in the well casing, theresistance of such fiuid cannot inadvertently expand the piston grippingelements 24 and the packing structure '57 against the wall of the wellcasing, since the fluid force is disposed internally of the grippingelements 24, as well as externally thereof, and it is also preventedfrom acting on and moving the upper abutment or anchor body 19relatively downwardly toward the lower abutment 59, which would effect ashortening of the packing structure 57 and its outward expansion. Thedownward force imposed by the fluid on the anchor body 19 and the sleeve56 is not transmitted to the packing element 57, but, instead, isby-passed completely to the connector sleeve 69, the lower end of whichis in engagement with the body shoulder '72. Thus, the downward force istransmitted directly to the body 10 without being imposed on the packingelement 57. During upward movement of the 'appanatus in the well casing,the fluid passing through the annular passage 2t? and around the packingstructure 57 does not tend to move the lower abutment 59 upwardly towardthe anchor body 19, but, instead, actually tends to hold the lowerabutment in a downward position in which the packing sleeve is fullyretracted. The apparatus can be elevated in the well casing and removedentirely therefrom at the top of the hole.

It is, accordingly, evident that a subsurface well tool has beenprovided in which the mandrel or body 10 can be moved by the tubularstring B through a relatively long stroke with respect to the well toolparts surrounding it, for the purpose of securing opening and closing ofthe valve portion of the apparatus, setting of the lower slips 62, andexpanding of its packing structure 57, and also closing of the annularpassage 20 so that the fluid pressure can shift the anchor grippingelements 24 outwardly into engagement with the well casing. Despite sucha long stroke, it is unnecessary to :move the balance sleeve 22 to thesame extent, which can be made comparatively short. The balance sleeveis only operatively connected to the body or mandrel It so as to beavailable for the purpose of counteracting the tendency of fluidpressure to shift the body or mandrel upwardly, after the stroke of themandrel 10 relative to the surrounding housing 21 has been substantiallycompleted. The valve device is pressure balanced so that it can beopened very readily even in the presence of a relatively high pressuredifferential imposed on the apparatus. The tubular string E can beelevated to elevate the body or mandrel 1d and dispose the latch devices46 opposite the release groove 47 in the housing or body 21, the latchfingers 46 then being carnmed into such groove to free them from themandrel 10, which is now free from "any restnaint imposed by the balancedevice 22 and capable of moving freely upwardly to elevate the valvehead 34 from and above the valve seat 36, thereby opening the annularpassage 26 through the apparatus.

I claim:

1. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped in said outer member; apiston movable within said outer member and along which said innermember is movable; and latch means connecting said piston to said innermember when said inner member is disposed in one position along saidpiston, said latch means disconnecting said piston from said innermember when said inner member is disposed in another position along saidpiston.

2. .ln apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped in said outer member; apiston movable within said outer member and along which one of saidmembers is movable; and latch means connecting said piston to said onemember when said one member is disposed in one position along saidpiston, said latch means disconnecting said piston from said one memberwhen said i one member is disposed in another position along the piston.

3. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped in said outer member;hydraulically operable means movable within said outer member and alongwhich said inner member is movable; and latch means connecting saidhydraulically operable means to said inner member when said inner memberis disposed in one position along said hydraulically operable means totransmit hydraulic force on said hydraulic operable means to said innermember; said latch means disconnecting said hydraulically operable meansfrom said inner member when said inner member is disposed in anotherposition along said hydraulically operable means.

4. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped in said outer member;hydraulically operable means movable within said outer member and alongwhich one of said members is movable; and latch means connecting saidhydraulically operable means to said one member when said one member isdisposed in one position along said hydraulically operable means, totransmit hydraulic force on said hydraulically operable means to saidone member, said latch means disconnecting said hydraulically operablemeans from said one member when said one member is disposed in anotherposition along said hydraulically operable means.

5. In apparatus adapted to be secured to a tubular running-in string foroperation in a well bore: first and second tubular members telescopedone within the other; means on said first tubular member for securingsaid first member to the tubular running-in string, whereby fluid underpressure in the tubular running-in string and first member tends toelevate said first member; hydraulically operable means in said secondmember along which said first member is movable and subject to fluidpressure substantially the same as the pressure of fluid in said firstmember and urged thereby in a downward direction; and releasable latchmeans connecting said hydraulically operable means to said first memberwhen said first member is disposed in one position along saidhydraulically operable means, whereby fluid pressure acting on saidhydraulically operable means urges said first member downwardly, saidlatch means disconnecting said hydraulically operable means from saidfirst member when said first member is disposed in another positionalong said bydraulically operable means.

6. In apparatus adapted to be secured to a tubular running-in string foroperation in a well bore: first and second tubular members telescopedone within the other and providing a fluid passage; coengageable valveelements on said members for controlling fluid flow through saidpassage; means on said first tubular member for securing said firstmember to the running-in string, whereby fluid under pressure in therunnin -in string and first member tends to elevate said first memberand disengage said valve elements from each other; hydraulicallyoperable means in said second member along which said first member ismovable and subject to fluid pressure substantially the same as fluidpressure in said first member and urged thereby in a downward direction;and releasable latch means connecting said hydraulically operable meansto said first member when said first member is disposed in one positionalong said hydraulically operable means with said valve elementscoengaged, whereby fluid pressure acting on said hydraulically operablemeans urges said first member downwardly and oflsets the fluid pressuretending to elevate said first member, said latch means disconnectingsaid hydraulically operable means from said first member when said firstmember is disposed in another position along said hydraulically operablemeans.

7. In apparatus adapted to be operated in a well bore: first and secondtubular members telescoped one within the other and providing a fluidpassage; coengageable valve elements on said members for controllingfluid flow through said passage; said first member being subject tofluid pressure in the well bore tending to move said first memberlongitudinally in one direction to disengage said valve elements fromeach other; hydraulically operable means in said second member alongwhich said first member is movable and subject to fluid pressure in thewell bore and urged thereby in the opposite longitudinal direction; andreleasable latch means connecting said hydraulically operable means tosaid first member when said first member is disposed in one positionalong said hydraulically operable means with said valve elementscoengaged, whereby fluid pressure acting on said hydraulically operablemeans urges said first member in said opposite longitudinal directionand oflsets the fluid pressure tending to move said first member in saidone longitudinal direction, said latch means disconnecting saidhydraulically operable means from said first member when said 12 firstmember is disposed in another position along said hydraulically operablemeans.

8. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengageable when saidinner member is in a lower position in said outer member and beingdisengaged from each other when said inner member is in an upperposition in said outer member; hydraulically operable means between saidmembers along which said inner member is movable and subject to fluidpressure in said passage and urged thereby in a downward direction; andreleasable latch means connecting said hydraulically operable means tosaid inner member when said inner member is disposed in said lowerposition in said outer member, said latch means disconnecting saidhydraulically operable means from said inner member when said innermember is disposed in said upper position in said outer member.

9. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengaged when saidinner member is disposed in one position in said outer member and beingdisengaged from each other when said inner member is disposed in anotherposition in said outer member longitudinally removed from said oneposition; said inner member being subject to fiuid pressure in the wellbore tending to move said inner member longitudinally in one directionin said outer member to said another position to disengage said valveelements from each other; hydraulically operable means between saidmembers along which said inner member is movable and subject to fluidpressure in said passage and urged thereby longitudinally in theopposite direction; and releasable latch means connecting saidhydraulically operable means to said inner member when said inner memberis disposed in said one position in said outer member, said latch meansdisconnecting said hydraulically operable means from said inner memberwhen said inner member is disposed in said another position in saidouter member.

10. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengageable when saidinner member is in a lower position in said outer member and beingdisengaged from each other when said inner member is in an upperposition in said outer member; a piston between said members along whichsaid inner member is movable and subject to fluid pressure in saidpassage and urged thereby in a downward direction; and releasable latchmeans secured to said piston and adapted to connect said piston to saidinner member when said inner member is dis posed in said lower positionin said outer member, said latch means disconnecting said piston fromsaid inner member when said inner member is disposed in said upperposition in said outer member.

11. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengageable when saidinner member is in a lower position in said outer member and beingdisengaged from each other when said inner member is in an upperposition in said outer member; a piston between said members along whichsaid inner member is movable and subject to fluid pressure in saidpassage and urged thereby in a downward direction; said inner memberhaving a groove; and releasable latch means secured to said piston andmovable into said groove to connect said piston to said inner memberwhen said inner member is disposed in said lower position in said outermember, said latch means being out of said groove to disconnect saidpiston from said inner member when said inner member is in said upperposition in said outer member.

12. In apparatus adapted to be operated in a Well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengaged when saidinner member is in one position in said outer member and beingdisengaged from each other when said inner member is in another positionin said outer member; said inner member being subject to fluid pressurein the well bore tending to move said inner member longitudinally in onedirection to said other position in said outer member to disengage saidvalve elements from each other; a piston between said members alongwhich said inner member is movable and subject to fluid pressure in saidpassage and urged thereby in the opposite longitudinal direction; saidinner member having a groove; and releasable latch means secured to saidpiston and movable into said groove to connect said piston to said innermember when said inner member is disposed in said one position in saidouter member, said latch means being out of said groove to disconnectsaid piston from said inner member when said inner member is in saidother position in said outer member.

13. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;coengageable valve elements on said members for controlling flow offluid through said passage, said elements being coengageable when saidinner member is in a lower position in said outer member and beingdisengaged from each other when said inner member is in an upperposition in said outer member; a piston between said members along whichsaid inner member is movable and subject to fluid pressure in saidpassage and urged thereby in a downward direction; said inner and outermembers having grooves; releasable latch means secured to saidpiston anddisposed in said outer member groove and movable from said outer membergroove into said inner member groove to connect said piston to saidinner member upon movement of said inner member to said lower positionin said outer member; and means on said inner member for shifting saidlatch means out of said inner member groove and into said outer membergroove upon movement of said inner member to said upper position.

14. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;

coengageable valve elements on said members for controlling floW offluid through said passage, said elements being coengaged when saidinner member is in one position in said outer member and beingdisengaged from each other when said inner member is in another positionin said outer member; said inner member being subject to fluid pressurein the well bore tending to move said inner member longitudinally in onedirection to said other position in said outer member to disengage saidvalve elements from each other; a piston between said members alongwhich said inner member is movable and subject to fluid pressure in saidpassage and urged thereby in the opposite longitudinal direction; saidinner and outer members having grooves; releasable latch means securedto said piston and disposed in said outer member groove and movable fromsaid outer member groove into said inner member groove to connect saidpiston to said inner member upon movement of said inner member to saidone position in said outer member; and means on said inner member forshifting said latch means out of said inner member groove and into saidouter member groove upon movement of said inner member to said otherposition.

15. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;a piston between said members along which said inner member ismovable'and subject to fluid pressure in said passage and urged therebyin a downward direction; said inner member having a groove; andreleasable latch means secured to said piston and movable into saidgroove to connect said piston to said inner member when said innermember is disposed in a lower position in said outer member, said latchmeans being out of said groove to disconnect said piston from said innermember when said inner member is in an upper position in said outermember.

16. In apparatus adapted to be operated in a well bore: an outer tubularmember; an inner tubular member telescoped within said outer member andproviding a fluid passage with said outer member disposed therebetween;a piston between said members along which said inner member is movableand subject to fluid pressure in said passage and urged thereby in adownward direction; said inner and outer member having grooves;releasable latch means secured to said piston and disposed in said outermember groove and movable from said outer member groove into said innermember groove to connect said piston to said inner member upon downwardmovement of said inner member in said outer member; and means on saidinner member for shifting said latch means out of said inner membergroove and into said outer member groove upon upward movement of saidinner member in said outer member.

References Cited in the file of this patent UNITED STATES PATENTS2,878,877 Baker Mar. 24, 1959 2,893,492 Brown July 7, 1959 2,962,096Knox Nov. 29, 1960

1. IN APPARATUS ADAPTED TO BE OPERATED IN A WELL BORE: AN OUTER TUBULARMEMBER; AN INNER TUBULAR MEMBER TELESCOPED IN SAID OUTER MEMBER; APISTON MOVABLE WITHIN SAID OUTER MEMBER AND ALONG WHICH SAID INNERMEMBER IS MOVABLE; AND LATCH MEANS CONNECTING SAID PISTON TO SAID INNERMEMBER WHEN SAID INNER MEMBER IS DISPOSED IN ONE POSITION ALONG SAIDPISTON, SAID LATCH MEANS DISCONNECTING SAID PISTON FROM SAID INNERMEMBER WHEN SAID INNER MEMBER IS DISPOSED IN ANOTHER POSITION ALONG SAIDPISTON.